Copy NEWS for 2.0.7 from branch.
* zh_CN.po: Translate "List of Listings"
* nn.po: Update from Ingar Pareliussen
Improve translation of "Graph" for achemso.layout

As discussed. achemso.layout contains both "Chart" and "Graph", therefore it
does not make sense to use "Graph" in the "Chart" / "Graph" / "Diagram" sense,
but in the mathematical sense like in "graph theory".
Therefore I added the context [[mathematicl]].
All translations are unchanged except the german one, which is now again
"Graph" as in 2.0.0 instead of "Schaubild".
* nl.po: Improve translation of Graph [[mathematical]]
Release notes: Remove entry about BibTeX errors

This feature has been disabled for this release.
Fix nn.po such that the statistic update script works
Update ANNOUNCE
Update INSTALL
Update it.po (thanks for the clarification, Georg)
French doc files: translations by Jean-Pierre
French Math.lyx: re-introduce 2 formulas that got accidentally lost by the last commit
Spanish manuals: translations by Ignacio
Additional.lyx: update version name to "2.1.x"
manuals: fix 2 typos spotted by Ignacio
fr.po: 3 shortcut conflicts by Jean-Pierre
Typo.
sk.po: Rechecked 'mathematical' context
Add news from 2.0.8.
* nn.po: Update from Ingar Pareliussen